Define the reason for the migration
Start with a measurable requirement such as reusing a native library or improving a supported workload. Compare download size, startup, memory, browser support and diagnostic complexity with the existing implementation. A format migration can add maintenance cost even when it makes casual source reading less convenient.
Describe what the module contains: a public codec, an offline calculation, a proprietary algorithm or a UI helper carry different constraints. If offline operation requires the full decision process on a customer device, plan around the fact that the customer receives that implementation.
Map the JavaScript boundary
Review the module’s imports, exports and surrounding JavaScript glue. A narrow compiled core can still reveal its purpose through function calls, buffers, constants, error messages and API requests. A network trace may show the workflow even if names inside the module are absent.
A concrete example is a local pricing preview. WASM can compute a preview efficiently, but the server must independently validate the order and calculate any authoritative charge. Trusting a client-returned total is an authorization problem regardless of whether the client used JavaScript or WASM.
Validate compatibility before exposure experiments
Keep fixed input/output vectors and error cases for the compiled logic. Exercise browser integration, worker use if relevant, cancellation, memory limits and deployment content types. Preserve an appropriate private diagnostic path so an implementation change does not make production failures impossible to understand.
When testing analyzer behavior, record the module size, tool versions and exact analysis path. A missing disassembler, an input limit or a failed parser does not establish that every analysis route is blocked. Score successful runtime behavior separately from analysis-tool failures.
Use the audit for its documented scope
CloneGuard can identify WASM artifacts and screen supported local bytes for known exposure patterns. It does not compile JavaScript into WASM, virtualize arbitrary code, validate all imported functions or prove semantic resistance to reconstruction. An opaque container or scan limit must remain an explicit gap.
Keep release receipts for the final artifact and its public loader. They can detect unintended file changes relative to a trusted inventory. They cannot stop a recipient from copying the module, inspecting its behavior or implementing an independent program that produces similar results.
Include the host boundary in the experiment
A module can pass its pure computation vectors while integration still exposes extra information or fails under real traffic. Test the host’s buffer lengths, encoding, ownership rules and error translation using controlled inputs. Review whether imported logging or debug functions reveal intermediate values. When a release changes the module and its JavaScript glue together, keep them under one release identifier and test the pair. A receipt covering only the .wasm file does not detect a modified loader. Document whether the experiment evaluated the whole browser feature or only a standalone compiled function.
Practical checklist
- Name the performance or reuse goal for WASM.
- Review imports, exports and JavaScript glue.
- Test fixed vectors, memory behavior and supported browsers.
- Keep authority server-side and report analyzer limits honestly.
Sources and further reading
Primary references support the technical details. Procedures here are guidance; only explicitly recorded project results describe tests we ran.
Prepared with AI assistance. How this library is produced. Suggest a correction; keep private code and credentials out of public issues.